A human heart is a vital part of the body having four chambers, the left and right atria and the left and right ventricles. The chambers alternately expand and contract to pump blood through the body. Each chamber of the heart includes a heart valve that, when functioning properly, controls the flow of blood in only one direction through the heart. However, the heart valve can become diseased or otherwise deficient such that it fails to close properly during the contraction of the lower chamber.
Mitral regurgitation is an insufficiency of a mitral valve which occurs when the mitral valve separating the left atrium and the left ventricle does not close properly when the heart pumps out blood. As a result, upon contraction of the left ventricle, blood may abnormally leak (regurgitate) from the left ventricle back into the left atrium, rather than flowing properly to the aorta. Mitral regurgitation can cause dilation of the left-sided heart chambers which, if left untreated, can ultimately lead to potentially fatal heart-rhythm disturbances and heart failure.
Another common heart disorder is aortic insufficiency, such as, for example, aortic stenosis in which the aortic valve located between the left ventricle and the aorta can become abnormally narrowed or constricted (stenotic) and therefore does not open fully. This can decrease the blood flow from the heart and lead to serious heart complications.
Heart valve regurgitation and other heart valve conditions can be caused by a variety of disorders and often require a surgical intervention involving replacement of a natural heart valve or heart replacement. An open heart procedure has been typically performed to surgically repair or replace a diseased or deficient heart valve using, for example, a prosthetic heart valve. However, an open heart surgery has significant risks and can lead to many complications. Moreover, some patients (e.g., children, elderly, patients with chronic conditions, etc.) can be at particular risk for open heart surgery and cannot be treated using this approach.
More recent approaches have been developed that aim at avoiding invasive valve repair or replacement surgeries by delivering a prosthetic valve using a catheter. However, a natural heart valve, such as a mitral valve, has a complicated anatomy and deforms in a complicated manner with the cardiac rhythm. The existing approaches do not adequately mimic the functionality of the mitral valve and may not address such potential issues as, for example, tissue damage, cardiac remodelling and paravalvular leaking. Furthermore, the techniques developed up-to-date may not provide adequate ways for replacing a heart valve implant after its deployment.
Accordingly, there remains a need for improved methods and systems for delivering prosthetic heart valves in a non-invasive manner.